From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f198.google.com (mail-wr0-f198.google.com [209.85.128.198]) by kanga.kvack.org (Postfix) with ESMTP id 7966E6B02F4 for ; Tue, 6 Jun 2017 07:13:51 -0400 (EDT) Received: by mail-wr0-f198.google.com with SMTP id t30so13209794wra.7 for ; Tue, 06 Jun 2017 04:13:51 -0700 (PDT) Received: from lhrrgout.huawei.com (lhrrgout.huawei.com. [194.213.3.17]) by mx.google.com with ESMTPS id x12si15609536wme.9.2017.06.06.04.13.49 for (version=TLS1 cipher=AES128-SHA bits=128/128); Tue, 06 Jun 2017 04:13:50 -0700 (PDT) Subject: Re: [PATCH 4/5] Make LSM Writable Hooks a command line option References: <20170605192216.21596-1-igor.stoppa@huawei.com> <20170605192216.21596-5-igor.stoppa@huawei.com> <71e91de0-7d91-79f4-67f0-be0afb33583c@schaufler-ca.com> <201706060550.HAC69712.OVFOtSFLQJOMFH@I-love.SAKURA.ne.jp> <201706061954.GBH56755.QSOOFMFLtJFVOH@I-love.SAKURA.ne.jp> From: Igor Stoppa Message-ID: <6c807793-6a39-82ef-93d9-29ad2546fc4c@huawei.com> Date: Tue, 6 Jun 2017 14:12:26 +0300 MIME-Version: 1.0 In-Reply-To: <201706061954.GBH56755.QSOOFMFLtJFVOH@I-love.SAKURA.ne.jp> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Tetsuo Handa , casey@schaufler-ca.com, keescook@chromium.org, mhocko@kernel.org, jmorris@namei.org Cc: paul@paul-moore.com, sds@tycho.nsa.gov, hch@infradead.org, labbott@redhat.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com On 06/06/17 13:54, Tetsuo Handa wrote: [...] > "Loading modules which are not compiled as built-in" is correct. > My use case is to allow users to use LSM modules as loadable kernel > modules which distributors do not compile as built-in. Ok, so I suppose someone should eventually lock down the header, after the additional modules are loaded. Who decides when enough is enough, meaning that all the needed modules are loaded? Should I provide an interface to user-space? A sysfs entry? [...] > Unloading LSM modules is dangerous. Only SELinux allows unloading > at the risk of triggering an oops. If we insert delay while removing > list elements, we can easily observe oops due to free function being > called without corresponding allocation function. Ok. But even in this case, the sys proposal would still work. It would just stay unused. -- igor -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org